a customizable value inspector that uses hexadecimal literals

Usage no npm install needed!

<script type="module">
  import eyesEs6Compat from 'https://cdn.skypack.dev/eyes-es6-compat';



a customizable value inspector for Node.js


I was tired of looking at cluttered output in the console -- something needed to be done, sys.inspect() didn't display regexps correctly, and was too verbose, and I had an hour or two to spare. So I decided to have some fun. eyes were born.


example of the output of a user-customized eyes.js inspector

eyes also deals with circular objects in an intelligent way, and can pretty-print object literals.


var inspect = require('eyes').inspector({styles: {all: 'magenta'}});

inspect(something); // inspect with the settings passed to `inspector`


var eyes = require('eyes');

eyes.inspect(something); // inspect with the default settings

you can pass a label to inspect(), to keep track of your inspections:

eyes.inspect(something, "a random value");

If you want to return the output of eyes without printing it, you can set it up this way:

var inspect = require('eyes').inspector({ stream: null });

sys.puts(inspect({ something: 42 }));


These are the default styles and settings used by eyes.

styles: {                 // Styles applied to stdout
    all:     'cyan',      // Overall style applied to everything
    label:   'underline', // Inspection labels, like 'array' in `array: [1, 2, 3]`
    other:   'inverted',  // Objects which don't have a literal representation, such as functions
    key:     'bold',      // The keys in object literals, like 'a' in `{a: 1}`
    special: 'grey',      // null, undefined...
    string:  'green',
    number:  'magenta',
    bool:    'blue',      // true false
    regexp:  'green',     // /\d+/

pretty: true,             // Indent object literals
hideFunctions: false,     // Don't output functions at all
stream: process.stdout,   // Stream to write to, or null
maxLength: 2048           // Truncate output if longer

You can overwrite them with your own, by passing a similar object to inspector() or inspect().

var inspect = require('eyes').inspector({
    styles: {
        all: 'magenta',
        special: 'bold'
    maxLength: 512